Method of forming relief structures

Abstract

A method of forming a relief pattern on the surface of a substrate comprises the steps of providing a substrate, coating a thin layer of polymeric material onto the substrate, drying the polymeric material to leave residual lateral stress within the material, bringing a patterned stamp into contact with the polymeric material and applying pressure to the stamp such that the polymeric material ruptures patternwise and dewets at the surface of the substrate to form openings in the polymeric layer according to the pattern on the stamp.

1 . A method of forming a relief pattern on the surface of a substrate comprising the steps of providing a substrate, coating a thin layer of polymeric material onto the substrate, drying the polymeric material leaving residual lateral stress within the material, bringing a patterned stamp into contact with the polymeric material, applying pressure to the stamp such that the polymeric material ruptures patternwise and dewets at the surface of the substrate to form openings in the polymeric layer according to the pattern on the stamp. 
   
   
       2 . A method of  claim 1  wherein the layer of polymeric material has a thickness of less than 100 nm, 
   
   
       3 . A method of  claim 1  wherein the layer of polymeric material has a thickness of between 10 nm and 60 nm. 
   
   
       4 . A method of  claim 1  wherein the temperature of the layer of polymeric material is below glass transition temperature at the time of the stamp being brought into contact therewith. 
   
   
       5 . A method of  claim 1  wherein the patterned stamp is provided with tapered edges 
   
   
       6 . A method of  claim 1  wherein the stamp is provided with an array of pinning points on the surface thereof to limit dewetting. 
   
   
       7 . A method of  claim 1  wherein the polymeric material is chosen from polystyrene, PMMA or P3HT. 
   
   
       8 . A method of  claim 1  wherein crosslinking agents and/or UV or curing agents are added to the polymeric material prior to the patterned stamp coming into contact therewith. 
   
   
       9 . A method of  claim 1  wherein the surface of the substrate has an average roughness of 5 nm, preferably less than 1 nm. 
   
   
       10 . A method of  claim 1  wherein the relief pattern is transferred to a receiver substrate.